Radioactivity smear sampler



Jan. 22, 1963 w. s. Moos RADIOACTIVITY SMEAR SAMPLER 2 Sheets-Sheet 1Filed April 20, 1959 Fig.1

Walter S. Moos 1N VEN TOR. M 06k- BY Zn aw 3m Jan. 1963 w. s. Moos3,074,276

RADIOACTIVITY SMEAR SAMPLER Filed April 20, 1959 2 Sheets-Sheet 2 Fig.5

Waller S. Moos Mm BY M 1N VEN TOR.

Unite States atent Ofilice 3,'M,2?ii Patented Jan. 22, 1963 Thisinvention relates to new and useful improvements in the means andtechniques for preparation of samples for both bacteria andradioactivity count.

Although the principal application of the invention 1s in connectionwith the preparation of a counting sample for radioactivity suspectedsubstances, it is to be clearly understood that the principles of theinvention are equally applicable with other substances such as thosewith which bacteria count is the objective.

If areas such as walls, tables, floors, etc. are suspected to becontaminated with radioactive dust, flakes, deposits from evaporatedliquids or other forms of radioactive contamination, the usual procedureis to collect samples of such material using filter or blotting paper.This paper is smeared over the area suspected to be contaminated, andthe paper is cut in small disks to fit planchets which in turn areplaced under a Geiger-Mueller counter or a scintillation probe and theactivity is determined.

The invention improves the technique. Many of the steps necessary withthe conventional methods are avoided, saving a considerable amount oftime and better results are achieved. One of the samplers or thisinvention is placed on the suspected area and the inside disk of thesampler is strongly depressed with one finger. In this way the adhesivecovering on the disk surface will make contact with the contaminant andretain it when the sampler is pulled oif the walls, table tops, etc. Aninner disk in the assembly of this invention will snap back due to thespring action associated with it and automatically will protect thecollected sample from being lost in part or whole by touching or rubbingthe collecting surface. The adhesive can be a single use type whichmeans discarding the sampler after it is used or it can be of a multipleuse construction employing pressure sensitive tape, such as Scotch brandcellophane adhesive tape with an adhesive on both sides. After one use,the thin contaminated tape can be pulled off and replaced with a newtape without discarding the rest of the sampler mechanism.

The sampler of this invention may be mounted on top of another providingfurther protection against loss of the samples. The usual methods havethe filter paper smears placed in envelopes and the material is oftenlost during carrying or manipulations. This difficulty is completelyavoided by use of this invention.

To summarize some of the advantages of the invention:

(1) Always known sample area covered with collected material. In the oldmanner the sample size varied with which fingers were used, pressureapplied etc., and the results were spotty coverings of differentthickness of collected material.

(2) The samples with the new instrument are more uniform in thickness.

(3) Points 1 and 2 facilitate calculation of activity per unit area (noirregular areas like finger prints).

(4) No rubbing through of paper on rough surfaces.

(5) Collected dust particles adhere strongly to the adhesive surface andwill not be removed very easy by air drafts etc. In this manner, crosscontamination or contamination of counters etc. becomes virtuallyimpossible.

(6) No blowing away of loose smear papers.

(7) No problem of transporting a larger number of samples.

(8) No placing of individual Smear samples into envelopes, etc.

(9) Not space consuming.

(10) No tedious cutting of paper.

(11) No further handling. Can be placed directly into counter.

Accordingly, an object of the invention is to improve the techniques ofhandling samples by means of a novel structural sampler which not onlyfacilitates the collection of the sample but also protects the sampleduring the whole and entire procedure involved with the sample.

These together with other objects and advantages which .will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a vertical stack of samplers shown in elevation, parts beingbroken away in section to show how the samplers may be nested with eachother for storage prior to use or after use.

FIGURE 2 is a sectional view of atypical sampler showing it in use.

FIGURE 3 is a sectional view of the same sampler in FIGURE 2 but showinga second step in the use of the sampler.

FIGURE 4 is an exploded pler in FEGURE 2.

FIGURE 5 is a front elevational view of a conventional counter with thedoor open showing the sample in place on a sampler holder as it would bepositioned for radioactivity counting.

FIGURE 6 is a top view of a modification of the sampler.

FIGURE 7 is an enlarged fragmentary sectional view taken on the line 77of FIGURE 6.

In the accompanying drawings there is illustrated a conventional counter10. This radioactivity counter is not only conventional but is merely aselected one of a number of commercially available counters whichoperate on different principles, for instance scintillation counting,Geiger-Mueller counters which operates on a different principle fromthat of a scintillation counter, etc. There is one feature common to allof the counters with which the invention is applicable and that is(insofar as the invention is concerned) a holder 12 of one type oranother on which a sampler is supported.

Sampler 14 (FIGURE 5) is shown in place on holder 12. The specificconstruction of the sampler constitutes what is deemed to be a majorimprovement in the handling of radioactivity suspected bearing material.Sampler 14 is made of a holder body 16. The holder body has acylindrical outer wall 18, and an end wall 29 extending across one endof the cylindrical wall I8. Wall 21' has a central aperture 22 throughwhich the finger of the user (FIGURE 2) may be projected. Acircumferential shoulder 2 is inset slightly from the surface of wall 18and forms a key with which to engage an adjacent sampler (FIGURE 1) whenthe samplers are stacked.

Disk 26 is mounted within the casing of the sampler. The disk ispreferably circular but has a lateral flange 28 at its inner end formingan abutment against which coil spring 30 seats. One end of the coilspring is seated on the abutment formed by flange 28, and the other endof the spring is disposed in a circumferential groove 32 in the insidesurface of cylindrical wall 18. This holds the spring captive withincavity 34 of the sampler, and the bias of the spring is in a directionwhich pushes disk 26 to a rest position against the inside surface 40 ofwall 2% (FIGURE 2).

An adhesive film 42 of non-drying pressure sensitive adhesive is appliedto the front face of disk 26. This adhesive is the collection andretaining agent for the dust, dirt, particles etc. suspected of beingcontaminated with radioactive material, or Whose bacteria count is to betaken, etc.

In use, the sampler is placed on the surface 44 suspected perspectiveview of the samiient means react.

of being contaminated or from which a sample is to be taken for otherpurposes. When in this position (FIG- URE 3) disk .26 is retractedwithin cavity 34. The user simply pushes on the face 48 of disk 26, forexample with one finger as shown in FIGURE 2, thereby pushing the diskoutwardly of the open end 50 of casing 16. This is against the yieldingopposition of spring 39. By applying enough pressure and holding thecasing, the adhesive film 42 on the disk comes to bear against thesurface 44 and collects the sample.

Adhesive film 42 may be of any available material which will serve thepurpose, there being at the present time numerous non-drying syntheticand/ or natural adhesives which will serve the purpose. The adhesivefilm 42 is subject to a number of variations. It may be applied to theface of disk 26 directly, applied to a flexible and pliable sheet ofpaper 54 (FIGURE 4) which is united to disk 26 or as shown in FIGURE 6,the adhesive film 42 may be a portion of a paper or other type ofmaterial disk 60 separably attached to the disk 26. A very satistactoryarrangement (FIGURES 6 and 7) is to have pressure sensitive adhesivedisks or tapes used where thedisk or tape is furnished with adhesive onboth surfaces thereof. Then the disk which has the adhesive surface 42thereon may be simply peeled from the disk 26 in order to enable it tobe replaced by another quantity of adhesive material so that the supportmay be re-used.

The support may be constructed so inexpensively that it could well be adisposable device to be discarded after a single use. For this reasoncommercially available plastics may be used to construct all parts ofthe sampler except the spring and of course, the adhesive and even here,the adhesive may be made of a plastic type substance.

As shown in FIGURE 1 the samplers can be nested in a stack. In such anarrangement the shoulder part 24 of wall 20 nests within the open end 50of an adjacent sampler thereby stacking neatly and securely.

The foregoing is considered as illustrative only of the principles ofthe invention. modifications and changes will readily occur to thoseskilled in the art, it is not desired to limit the invention to theexact construction and operation shown and described, and accordinglyall suitable modifications and equivalents may be resorted to, fallingwithin the scope of the invention as claimed.

What is claimed as new is as follows:

1. A sampler comprising a casing having wall means defining a cavity, anend wall at one end of said wall means having an aperture through whichthe finger of a user may be projected, a movable member in said cavityand on which an adhesive film is secured and means disposed within saidcasing for yieldingly opposing movement of the movable member by theusers finger toward a test surface to be contacted 'by the adhesive filmand operative to retract said movable member with the adhesive filmthereon from the test surface upon release thereof by the users finger.

2. The sampler of claim 1, wherein said last mentioned means includes aspring connected with said wall means and reacting on said member toyieldingly oppose the movement of said member with reference to saidcasing.

3. The sampler of claim 1 wherein said last mentioned means includes aspringconnected with said wall means and reacting on said member. toyieldingly oppose the movement of said member with reference to saidcasing in one direction and hold said member in a normally retractedposition within said casing.

4. The sampler of claim 3 wherein said member consists of a disk havinga lateral flange on which said resil- 5. A sampler comprising'a casinghaving a side wall and. defining a cavity, an end wall at the end of thefirst mentioned wall and having an aperture through which the finger ofa user may be projected, a movable member in said cavity and on which anadhesive film is secured,

Further, since numerous spasms a spring connected with said firstmentioned wall and reacting on said member to yieldingly oppose themovement of said member with reference to said casing in one directionand hold said member in a normally retracted position within saidcasing, said end wall having a shoulder set in from the outer surface ofthe first mentioned wall to for-m a key within which to fit into theadjacent open end of an adjacent sampler so that the samplers may benested in a column.

6. A sampler for suspected contaminated substances, said samplercomprising a casing having wall means which defines a cavity, a membermounted for movement in said cavity, said wall means having an open endthrough which a portion of said member is projectible, an adhesivesubstance on the portion of said member which is projectible through theopen end of said wall means, said adhesive substance being adapted toaccumulate and hold a sample and means mounted in the casing operativelyconnected to said member for biasing the member to a retracted positionwith the adhesive substance and samples protectively enclosed by thecasing.

7. The sampler of claim 6, wherein said last mentioned means includes aresilient means reacting on said casing and said member to yieldinglyoppose the movement of said member in one direction.

8. The sampler-of claim 6 wherein said last mentioned means includesresilient means reacting on said casing and said member to yieldinglyoppose the movement of said member in one direction, and retract saidmember Within said casing. i

9. The sampler of claim 6 wherein said last mentioned means includesresilient means reacting on said casing and said member to yieldinglyoppose the movement of said member in one direction, and retract saidmember within said casing, said Casing having an end wall against whichsaid member normally rests and is retained by the action of saidresilient means. i

10. The sampler as defined in claim 9, including means connected withsaid casing to engage an adjacent sampler and hold the samplers innested relationship with each other.

11. The sampler of claim 10 wherein said end wall has a finger receivingaperture therein to receive the finger of the user in projecting themember outwardly of said casing against the yielding opposition of saidresilient means.

12. The combination of claim 11 wherein said resilient means consists ofa spring reacting on a portion of said casing and on a portion of saidmember.

13. A sampler for suspected contaminated substances,

said sampler comprising a casing having a side wall which defines acavity, a member mounted for movement in said casing, said casing havingan open end through which a portion of said member is projectible, anadhesive film on the portion of said member which is projectible throughthe open end of said casing and onto which to accumulate and hold asample, resilient means reacting on said casing and said member toyieldingly oppose the movement of said member in one direction, andretract said member within said casing, said casing having an end wallagainst which said member normally rests and is retained by the actionof said resilient means, said adhesive film having a backing thereon foradhering the film'to said member when the member is both projectedagainst a surface and then retracted, said backing being removable fromthe member for substitution by another adhesive film bearing backing.

References Cited in the file of this patent UNITED STATES PATENTS

1. A SAMPLER COMPRISING A CASING HAVING WALL MEANS DEFINING A CAVITY, ANEND WALL AT ONE END OF SAID WALL MEANS HAVING AN APERTURE THROUGH WHICHTHE FINGER OF A USER MAY BE PROJECTED, A MOVABLE MEMBER IN SAID CAVITYAND ON WHICH AN ADHESIVE FILM IS SECURED AND MEANS DISPOSED WITHIN SAIDCASING FOR YIELDINGLY OPPOSING MOVEMENT OF THE MOVABLE MEMBER BY THEUSER''S FINGER TOWARD A TEST SURFACE TO BE CONTACTED BY THE ADHESIVEFILM AND OPERATIVE TO RETRACT SAID MOVABLE MEMBER WITH THE ADHESIVE FILMTHEREON FROM THE TEST SURFACE UPON RELEASE THEREOF BY THE USER''SFINGER.